* Megalith: A large, prehistoric stone monument.
* Megastar: A very famous and successful celebrity.
* Megaphone: A cone-shaped device used to amplify sound.
* Megafauna: Very large animals, especially those that lived in the past.
* Megacity: A city with a population of over 10 million people.
* Megawatt: A unit of power equal to one million watts.
* Megabytes: A unit of data equal to one million bytes.
* Megalomania: An obsessive belief in one's own power and importance.
* Megalopolis: A very large urban area made up of several cities.
These are just a few examples. The prefix "mega" is often used to indicate something large or powerful, so you can find many other words with this prefix that have a similar meaning.